Method for preparing imides from sulfonyl fluorides

ABSTRACT

This invention discloses a method for preparing imides (I) and (IT) from compounds having a sulfonyl fluoride func

FIELD OF THE INVENTION

[0001] This invention is directed to a method for preparing imides fromcompounds having a sulfonyl fluoride fuinctional group. The imides soprepared are useful in a variety of catalytic and electrochemicalapplications.

BACKGROUND OF THE INVENTION

[0002] Compounds having a sulfonyl fluoride fuinctional group are wellknown in the art. In particular, vinyl ethers and olefins having afluorosulfonyl fluoride group have been found to be particularly usefuilas monomers for copolymerization with tetrafluoroethylene, ethylene,vinylidene fluoride and other olefinic and fluoroolefinic monomers toform polymers which, upon hydrolysis are converted to highly usefulionomers. One area of important use for jonomers so formed is in thearea of lithium batteries. See for example Connolly et all U.S. Pat. No.3,282,875 and commonly assigned Ser. Nos. 09/023,244 and Ser. No.09/061,132.

[0003] It is also known to prepare imides from compounds having sulfonylfluoride functionality particularly fluorinated organic sulfonyl inmidesare known in the art. For example, DesMarteau, U.S. Pat. No. 5,463,005,discloses substituted perfluoro-olefins of the formula

[0004] where X=CH or N, Z=H, K, Na, or Group I or II metal, R=one ormore fluorocarbon groups including fluorocarbon ethers and/or sulfonylgroups and/or perfluoro non-oxy acid groups, Y=perfluoroal or F, and m=0or 1.

[0005] Xue, Ph.D. thesis, Clemson University, 1996, discloses theformation of the monomer

CF ₂ =CF−OCF ₂ CF ₂ SO ₂ N(Na)SO ₂ CF ₃

[0006] by reaction of CF₂ =CF−OCF₂CF₂SO₂Cl with CF₃SO₂NHNa in thepresence of Na₂CO₃ in acetonitrile. However, Xue's method is notapplicable to the sulfonyl fluoride species without first protecting thedouble bond.

[0007] Further disclosed by Xue, op.cit, is CF₃SO₂NNa₂ made by combiningCF₃SO₂NHNa and NaH in THF and reacting for four hours at roomtemperature. The inventors hereof have determined that Xue's method ofpreparation provides a conversion of less than 10% from CF₃SO₂NHNa toCF₃SO₂NNa?. No method of separation is provided, nor is any methodprovided for preparing the CF₃SO₂NNa₂ at higher yield. Thus no means isprovided for producing CF₃SO₂NNa₂ in a highly purified state. Xuesuggests that CF₃SO₂NNa₂ can be reacted with a cyclic sulfone of theformula

[0008] to produce the vinyl ether monomer, CF₂=CF−OCF₂CF₂SO₂N(Na)SO₂CF₃.Also disclosed by Xue is a reaction between CF₂=CFOCF₂CF₂SO₂F andCF₃SO₂NHNa to produce an unusable complex mixture of products. Xue makesno suggestion that CF₃SO₂NNa₂ is effective at converting sulfonylfluoride containing compounds to imides.

[0009] MeuBdoerffer et al., Chemiker Zeitung, 96. Jahrgang (1972) No.10, 582-583 discloses a method for synthesizing RSO₂NH₂ wherein R isperfluoroalkyl.

[0010] Feiring et al., WO 9945048(A1), provides a method for imidizingfluorinated vinyl ether monomers containing a sulfonyl fluoride group byfirst protecting the double bond and then converting the sulfonylfluoride into an imide.

[0011] Armand et al, EPO 0 850 920 A2. discloses a method for imidizingsulfonyl fluoride and chloride species containing aromatic rings.

SUMMARY OF THE INVENTION

[0012] The present invention provides for a process comprising:Contacting, in a liquid dispersion or solution, a composition comprisinga sulfonyl amide salt represented by the formula:

(R ² SO ₂ NM _(b))_(3−b) M′ _(c)(III)

[0013] wherein R² is aryl, fluoro-aryl, or XCF₂−where X is H, halogen,fluorinated or non-fluorinated linear or cyclic alkyl radicals having1-10 carbons, optionally substituted by one or more ether oxygens, M′ isan alkaline earth metal, b=1 or 2, c=0 or 1, M is an alkaline earth whenb is 1 or an alkali metal when b is 2 and c =0, and M is alkali metalwhen b=1 and c=1, with the proviso that c is not equal to 1 when b=2with a non-polymeric sulfonyl fluoride composition represented by theformula R¹(SO₂F)_(m) (IV) wherein m=1 or 2, where, when m=1, R¹ is afluorinated or non-fluorinated, saturated or unsaturated hydrocarbylradical, except perfluoroolefin, having 1-12 carbons optionallysubstituted by one or more ether oxygens, or tertiary amino; or, whenm=2, R¹ is a fluorinated or non-fluorinated, saturated or unsaturatedhydrocarbylene, except perfluoroalylene, radical having 1-12 carbonsoptionally substituted by one or more ether oxygens; or with a polymericsulfonyl fluoride composition comprising monomer units represented bythe formula

—[CZ ₂ CZ(R ³ SO ₂ F)]—  (V)

[0014] wherein R³ is a diradical selected from the group consisting offluorinated or non-fluorinated allylene, including oxyalkylene orfluorooxyalkylene, but not perfluoroalkylene, and each Z isindependently hydrogen or halogen, and the Zs need not be the same; and,causing them to react to form a non-polymeric imide compositionrepresented by the formula

[0015] wherein y=1 or 2, M is an alkali when y is 1 or an alkaline earthmetal when y is 2, m=1 or 2, where, when m=1, R¹ is a fluorinated ornon-fluorinated, saturaw&or unsaturated hydrocarbyl radical, exceptperfluoroolefin, having 1-12 carbons optionally substituted by one ormore ether oxygens, or tertiary amino; or, where m=2, R¹ is afluorinated or non-fluorinated, saturated or unsaturated hydrocarbylene,except perfluoroalkylene, radical having 1-12 carbons optionallysubstituted by one or more ether oxygens, with the proviso that when y=2and m=2, M may represent a combination of alkali and alkaline earthmetals; or, in the alternative, a polymeric imide composition comprisingmonomer units represented by the formula

[0016] wherein y=1 or 2; R³ is a diradical selected from the groupconsisting of fluorinated or non-fluorinated alkylene, includingoxyalkylene or fluorooxyalkylene, each Z is independently hydrogen orhalogen, wherein the Z's need not be the same; R² is aryl, fluoro-aryl,or XCF₂—where X is H, halogen, fluorinated or non-fluorinated linear orcyclic alkyl radicals having 1-10 carbons, optionally substituted by oneor more ether oxygens; M is an alkali when y is 1 or an alkaline earthmetal when y is 2.

[0017] As used herein, the term “reacting” is intended to mean allowingor to allow at least two components in a reaction mixture to react toform at least one product. “Reacting” may optionally include stirringand/or heating or cooling.

BRIEF DESCRIPTION OF DRAWING

[0018]FIG. 1 is a representation of the apparatus employed fordetermining the volume of hydrogen gas evolved from the reactionsdescribed in the specific embodiments herein.

DETAILED DESCRIPTION

[0019] The process of the present invention represents a simple methodof providing a very wide range of imides which can be readily andvariously ion exchanged to provide superacid catalysts, electrolytes,and ionomers useful for electrochemical applications.

[0020] In the practice of the invention it is not necessary to firstprotect the double bond of an olefinic or vinyl ether prior toimidization. The imidization will proceed without attacking the doublebond.

[0021] Equally useful is the imidizationdblhapolymer comprising monomerunits of vinylidene fluoride and monomer units comprising a pendantgroup having sulfonyl fluoride functionality, particularly aperfluorovinyl ether perfluoroalkoxysulfonyl fluoride, such as describedin Doyle et al., WO 9941292(A1). The methods of the art for convertingsulfonyl fluorides to imides are not applicable to the copolymers of WO9941292(A1) and others embodiments containing vinylidene fluoridemonomer units because of the base instability of the vinylidene fluoridemoiety. Application of the methods of the art result in extensive andunacceptable degradation of the polymer backbone in vinylidene fluoridecontaining polymers. The method of the present invention provides forconversion of sulfonyl fluoride to imide in vinylidene fluoridecontaining polymers without degradation of the polymer backbone.

[0022] In the present invention, the term “hydrocarbyl” is employed tomean a monoradical consisting of carbon and hydrogen. Included in theterm “hydrocarbyl” are alkyl, cycloalkyl, aryl, aryl alkyl and the like.Similarly, the term “hydrocarbylene” is employed to mean a diradicalconsisting of carbon and hydrogen. Both hydrocarbyl and hydrocarbyleneradicals, as employed herein, may contain one or more unsaturatedcarbon-carbon bonds, one or more ether oxygens, and may be partially orfully fluorinated. Essentially any hydrocarbyl or hydrocarbylene radicalis suitable for the practice of the invention except that radicalscontaining perfluorolefin finctionality are not suitable for thepractice of the invention. Perfluorovinyl ether functionality however ispreferred. Thus, the functional group CF₂=CF−CF₂— is not suitable butthe functional group CF₂=CF—O— is not only suitable but is alsopreferred.

[0023] In one aspect of the present invention, dimetal sulfonyl amidesalts having the formula (R²SO₂NM_(b))_(3-b)M′_(c) (III) are found to behighly effective agents for preparing imides from a wide variety ofcompounds having a sulfonyl fluoride functionality, both from polymericand non-polymeric species. In the dimetal sulfonyl amnide salts suitablefor the process of the invention, R² is aryl, fluoro-aryl, or XCF₂—where X is H, halogen, fluorinated or non-fluorinated linear or cyclicalkyl radicals having 1-10 carbons, optionally substituted by one ormore ether oxygens, M′ is an alkaline earth metal, b=1 or 2, c=0 or 1, Mis an alkaline earth when b is 1 or an alkali metal when b is 2 and c=0,and M is alli metal when b=1 and c=1, with the proviso that c is unequalto 1 when b=2.

[0024] Preferably, R² is fluoroalkyl having 1-4 carbons; most preferablyR² is CF₃—. Preferably, M is an alkali metal, most preferably sodium,and b=2.

[0025] In one embodiment, a non-polymeric sulfonyl fluoride compositionrepresented by the formula R¹(SO₂F)_(m) in liquid dispersion or solutionis contacted with the dimetal sulfonyl amide salt(III) to form areaction mixture. m=1 or 2, where, when m=1, R¹ is a fluorinated ornon-fluorinated, saturated or unsaturated hydrocarbyl radical having1-12 carbons optionally substituted by one or more ether oxygens, exceptperfluoroolefin, or tertiary amino; or, when m=2, R¹ is a fluorinated ornon-fluorinated, saturated or unsaturated hydrocarbylene, exceptperfluoroalkylene, radical having 1-12 carbons optionally substituted byone or more ether oxygens, preferably m=1. More preferably m=1, R¹ is aperfluorovinyl ether represented by the formula

CF ₂ =CF—O—[CF ₂ CF(R ⁴)—O _(z)]_(n) —CF ₂ CF ₂—

[0026] wherein R⁴ is F or perfluoroalkyl having 1-4 carbons, z=0 or 1,and n=0-3. Most preferably m=1 and R⁴ is trifluoromethyl, z=1, and n=0or 1.

[0027] In one embodiment, the process of the invention may be conductedin the absence of an inert liquid diluent when a sufficient excess of aliquid R¹(SO₂F)_(m) is provided to ensure good mixing. However, in theabsence of an inert diluent, the reaction may proceed inhomogeneously,and is potentially subject to sudden decomposition. Therefore, it ispreferred to conduct the process of the invention in an inert liquiddiluent. Numerous aprotic organic liquids are suitable for use as aninert liquid diluent for the process of the invention; the requirementsare not strict beyond liquidity and inertness. It is preferred to use asolvent that dissolves the monomer but not the NaF by-product so that itcan easily be filtered off. Preferred liquids are ethers, including THF,nitrites, DMSO, amides, and sulfolanes. Ethers are more preferred, withTHF most preferred.

[0028] The reaction may be conducted at any temperature between thefreezing and boiling point of the inert liquid diluent. Room temperaturehas been found to be satisfactory in the preferred embodiment of theinvention. Temperatures from room temperature to 80° C. are suitable,with room temperature to 60° C. more preferred.

[0029] The reaction mixture is preferably stirred or otherwise agitatedaccording to means commonly employed in the art.

[0030] In a first preferred embodiment of the process of the invention,the product of the process is most preferably as represented by theformula

CF ₂ =CFO—[CF ₂ CF(CF ₃)—O] _(n) —CF ₂ CF ₂ SO ₂ N(Na)SO ₂ CF ₃  (VIII)

[0031] where n=0 or 1. It is a particularly surprising aspect of thepresent invention that the conversion of the —SO₂F group may be effectedwithout the necessity of protecting the double bond. The productso-formed, (VIII), may advantageously be employed as a comonomer withfluorinated olefins, non-fluorinated olefins, fluorinated vinyl ethers,non-fluorinated vinyl ethers, and combinations thereof. Preferredcomonomers include ethylene, tetrafluoroethylene, hexafluoro-propylene,perfluoroalkyl vinyl ether, vinylidene fluoride, and vinyl fluoride.Copolyrnerizing the monomer (VIII) with a variety of co-monomers may beeffected for example according to the teachings of DesMarteau, op.cit.or of Feiring et al., op.cit. or, more broadly, may be effectedaccording the methods of Connolly et al., op. cit. The ionomers soformed are useful in a wide variety of electrochemical applications.

[0032] One area of particular utility is in lithium batteries. For thispurpose, the product monomer, (VIII), may be ion exchanged to thelithium form by contacting the monomer (VIII) with a dilute solution ofLiCI in THF. The polymerizations indicated above may then be effected.In the alternative, the polymerizations may first be effected, followedby ion exchange with LiCl in TBF. In an alternative embodiment, thepreferred sodium imide of the invention can be treated with aqueous acidto form the acid followed by treatment with aqueous lithium salt to formthe lithium ion composition.

[0033] In a further embodiment a sulfonyl fluoride polymer compositionis contacted with the dimetal sulfonyl amide salt (III) in liquiddispersion or solution to form a reaction mixture. The polymer comprisesmonomer units represented by the formula

—[CZ ₂ CZ(R ³ SO ₂ F)]—  (V)

[0034] wherein R³ is a diradical selected from the group consisting offluorinated or non-fluorinated alkylene, but not perfluoroalkylene,including oxyalkylene or fluorooxyalkylene, and each Z is independentlyhydrogen or halogen, and need not be the same. Preferably, R³ isoxyalkylene. In a second preferred embodiment (V) is represented by theformula

[0035] wherein R⁴ is F or perfluoroalkyl having 1-4 carbons, z=0 or 1,and a =0-3. Most preferably R⁴ is trifluoromethyl, z=1, and a=0 or 1.

[0036] The polymer comprising the moor units (IX) may comprise up to 50mol % of said monomer units (IX). Comonomer units incorporated therewithmay be derived from numerous olefinically unsaturated species asidentified in the art including, ethylene, vinylidene fluoride (VF₂)vinyl fluoride, and combinations thereof to form terpolymers. Additionaltermonomers include tetrafluoroethylene, hexafluoropropylene,perfluoroalkyl vinyl ethers, and such other ethylenically unsaturatedspecies as are known in the art.

[0037] Particularly preferred for the practice of the invention is acopolymer comprising up to 50 mol %, most preferably up to 20 mol %, ofcomonomer units (IX) and comonomer units derived from VF₂, mostpreferably at least 50 mol % of monomer units derived from VF₂. It is asurprising aspect of the present invention that the copolymer of (IX)with at least 50 mol % of units derived from VF₂ can be successfullyreacted according to the process of the invention to form thecorresponding imide. Because of the well-known base instability ofVF₂-containing polymers, the methods of the art for forming imides fromsulfonyl fluorides are not operable with polymers having any more thantrace amounts of monomer units derived from VF₂ because the imidizingagents of the art attack the polymer backbone causing extensivedegradation.

[0038] There is no particular limitation on the molecular weight ofpolymers suitable for the practice of the invention. Oligomeric polymersmay themselves be liquids at or near room temperature and therefore arewell-suited as the liquid dispersing medium of the process. However, itis generally preferred to employ an inert diluent, preferably a solventfor the polymer. As the molecular weight of the polymer increases,solubility and solution viscosity become increasingly difficultproblems, making homogeneous reaction difficult. The preferred copolymerof VF₂ and comonomer (IX) is particularly well-suited to the practice ofthe present invention because of the relatively higher solubility ofVF₂-containing polymers in non-fluorinated solvents than otherfluoropolymers.

[0039] Numerous aprotic organic liquids are suitable for use as solventsfor the sulfonyl fluoride polymer composition in the process of theinvention. As stated, solubility of the polymer reactant is a limitingfactor. Preferred solvents are ethers, including THF, nitriles, DMSO,amides, and sulfolanes. Ethers are more preferred, with THF mostpreferred. Because of the limitations on solubility associated with highmolecular weight, lower molecular weight polymers are preferred.

[0040] Suitable and preferred reaction temperatures are as in the caseof the non-polymeric reactant hereinabove described.

[0041] For the purposes herein, the polymer produced in the process ofthe invention is represented by the formula

[0042] wherein y=1 or 2; R³ is a diradical selected from the groupconsisting of fluorinated or non-fluorinated alkylene, includingoxyalkylene or fluorooxyalkylene, each Z is independently hydrogen orhalogen, wherein the Zs need not be the same; R² is aryl, fluoro-aryl,or XCF₂- where X is H, halogen, fluorinated or non-fluorinated linear orcyclic alkyl radicals having 1-10 carbons, optionally substituted by oneor more ether oxygens; M is an alkali when y=1 or an alkaline earthmetal when y=2. When y=2, M is an alkaline earth metal. Setting y=2 ismeant to designate that the alkaline earth metal, M in (II), which has avalence of 2, is bonded to two different polymer chains each of theindicated composition, thus serving as a metallic cross-link. It is alsopossible, depending upon chain configuration, for the alkaline earthmetal M to be bonded to two segments of the same polymer chain.

[0043] The process of the present invention is preferably practiced witha purified form of the dimetal sulfonyl amide salt (D). Xue, op.cit.,teaches only a process which provides very small amounts of highlycontaminated (II). The inventors of the present invention havedetermined by ordinary methods of chemical analysis that Xue's processproduced CF₃SO₂NNa₂ with conversion of less than 10%, most of theremainder of his reaction product being unconverted starting material.No method is provided in the art for preparing (III) in pure form.

[0044] In the process of the invention, the dimetal sulfonyl amide saltstarting material (R²SO₂NM_(b))_(3b)M'c, (II), should first itself beproduced at high yield. In (III), R² is aryl, fluoro-aryl, or XCF₂-where X is H, halogen, fluorinated or non-fluorinated linear or cyclicalkyl radicals having 1-10 carbons, optionally substituted by one ormore ether oxygens, M′ is an alkaline earth metal, b=1 or 2, c=0 or 1, Mis an alkaline earth when b=1 or an alkali metal when b=2 and c=0, and Mis kali metal when b=1 and c=1, with the proviso that c is not equal to1 when b=2.

[0045] Preferably, M is an alkali metal and c=0, b=2,-and R² is aperfluoroalkyl radical. Most preferably M is sodium and R² is atrifluoromethyl radical. The inventor hereof has found that surprisinglyhe dimetal sulfonyl amide salt (III) can be made at much higher puritiesthan in Xue's process, purity of greater than 50%, preferably greaterthan 90%, most preferably greater than 95%, by contacting a sulfonylamide or monometal sulfonyl amide salt thereof having the formula(R²SO₂NH)_(3-a)M″,(VII), with at least one alkali or allaline earthmetal hydride and an aprotic liquid to form a reaction mixture which ispermitted to react to any desired degree of conversion up to 100%, whichis preferred. In the sulfonyl amide or monometal salt thereof (VII), a=1or 2, m″ is alkaline earth metal when a=1, M″ is alkali metal orhydrogen when a=2, and R² is aryl, fluoro-aryl, or XCF₂- where X is H,halogen, or a fluorinated or non-fluorinated linear or cyclic alkylradical having 1-10 carbons, optionally substituted by one or more etheroxygens. In the hydride may be a mixture of more than one alkali oralkaline earth hydrides, or a mixture of alkali and alkaline earthhydrides. If preferred, the reaction may proceed in stages withdifferent hydrides being fed to the reaction at different times.

[0046] Preferably R² is perfluoroalkyl, most preferably trifluoromethyl,and M″ is sodium. CF₃SO₂NH₂ is the preferred starting material forpreparing the CF₃SO₂NNa₂ preferred for the process of the presentinvention. The preferred aprotic liquid is acetonitrile. Preferably thereaction to produce the CF₃SO₂NNa₂ is continued until one or the otherstarting material is completely consumed and reaction stops. Morepreferably the stoichiometry is adjusted so that only trace amounts ofeither starting material remain when reaction is complete. Mostpreferably, the hydride is added at slightly below stoichiometricquantity.

[0047] The sulfonyl amide and monometal salt thereof (VII) are solublein the aprotic solvents employed in the process of preparing the dimetalsulfonyl amide salt (HII), but the dimetal sulfonyl amide salt (III)itself is not. The solubility difference is exploited herein to separatethe reaction product from the reaction mixture and obtain a compositioncomprising sulfonyl amide salts at least 50 mol %, preferably at least90 mol %, most preferably at least 95 mol %, of which salts arerepresented by the formula (R²SO₂NM_(b))_(3-b)M_(c)′, (III), ashereinabove defined. Any convenient method known in the art forseparating solids from liquids may be employed, including filtration,centrifugation and, distillation.

[0048] While it is preferred to permit the synthesis of (III) to run tocompletion, this may not always be practical depending upon the aproticsolvent chosen. In neat acetonitrile, 100% conversion is achieved in ca.4 hours at room temperature. However, in neat THF, six days of reactionare required for 100% conversion. In the latter case, it may be desiredto separate the reaction product before the reactants have fullyreacted. The method of separation based upon the heretofore unknownsolubility difference hereinabove described provides a practical methodfor isolating the dimetal sulfonyl amide salt (III) at high purity whenconversion has been low.

[0049] It has been found in the practice of the present invention thatresidual hydride left over from the synthesis of the dimetal sulfonylamide salt (III) is not highly deleterious to the efficacy of theprocess of the present invention. While not critical, the CF₃SO₂NNa₂preferred for the process of the present invention is substantially freeof contamination by NaH. This is achieved by employing slightly lessthan the stoichiometric amount of NaH in its preparation, therebyinsuring that when the reaction achieves full conversion, the NaH willbe exhausted. Any excess of the soluble intermediate CF₃SO₂NHNa iseasily separated by washing/filtration cycles, preferably using freshaliquots of solvent.

[0050] In preparing the dimetal sulfonyl amide salt, (III) it has beenfound that the components of the reaction mixture may be combined in anyorder, but that it is preferred to first mix the sulfonyl amide or amonometal salt thereof (II), with the aprotic liquid to form a solution,following with addition of the hydride after the solution has formed.First mixing the hydride with the aprotic solvent has resulted in poorreaction or slower than expected conversion.

[0051] A suitable temperature for preparing the dimetal sulfonyl amidesalt (III) will lie between the melting point and the boiling point ofthe aprotic liquid selected. It has been found to be satisfactory forthe practice of the invention to conduct the process of the invention atroom temperature. However, somewhat higher temperatures result in fasterreaction. In the most preferred embodiment of the invention,acetonitrile is employed as the solvent at a temperature between 0° C.and 80° C., preferably between room temperature and 80° C., mostpreferably between room temperature and 60° C.

[0052] Aprotic solvents suitable for preparing the dimetal sulfonylamide salt (III) should be substantially free of water. Water causes thereaction to go in the wrong direction, for example to form CF₃SO₂NHNaand NaOH, and provides a route for making a sulfonate instead of animide. In a preferred embodiment, it has been found satisfactory toemploy acetonitrile having water content less than or equal to ca 500ppm, with water content less than or equal to ca. 50 ppm more preferred.Acetonitrile is quite hygroscopic, and care should be taken in handlingto avoid water contamination from the atmosphere.

[0053] The preferred aprotic solvent for the preparation of the dimetalsulfonyl amide salt (III) comprises acetonitrile. Acetonitrile has beenfound to accelerate the conversion by a considerable amount over otheraprotic solvents. In neat acetonitrile, essentially quantitativeconversion is achieved in ca. 4 hours. In the presence of as little as5% acetonitrile in the THF taught by Xue,op. cit., essentiallyquantitative conversion is achieved in ca. 25 h. These results contraststarkly with the six days required under the conditions taught by Xue.

[0054] It is found that solvent selection has a tremendous effect on therate of conversion, though most aprotic solvents will lead to highconversion over sufficient time. Acetonitrile is highly preferred. Otheraliphatic and aromatic nitrites, while suitable, do not appear to beparticularly better than the THF employed by Xue but may be employed assubstitutes for THF. Suitable nitrites include higher alkyl nitrites,dinitriles such as adiponitrile, benzonitrile, and the like. Othersuitable solvents include ethers, DMF, DMSO, DMAC, and amides.Combinations of suitable solvents are also suitable.

[0055] Any of the methods hereinabove, alone or in combination, providea highly purified form of the sufonyl amide salt (III) in dramaticdistinction over the practice of Xue. The highly purified form of(R²SO₂NM_(b))_(3-b)M′, (III), greater than 95% purity, which is readilyachieved using the methods herein described, is then suitable for use inthe process of the present invention producing pure imides, (I) or (II),at high yields, the purity thereof depending directly upon the purity of(III). Any of the methods of preparation herein described are capable ofproviding (III) in purities of greater than 95%.

[0056] The atmosphere to which the dimetal sulfonyl amide salt (III) isexposed should be substantially free of water as well. Water vaporconcentrations of about 25 ppm have been found to be highly suitable.Higher levels of water vapor concentration can be tolerated, but itshould be understood that the higher the water vapor concentration ofthe atmosphere, the greater the contamination during subsequentreaction. As a general rule, the less water, the better, in whateverform.

[0057] The term “inert atmosphere” as used herein refers to an anhydrousatmosphere having a water vapor concentration of less than ca. 50 ppm.It is not meant to imply a non-oxidative atmosphere. Thus, the reactionsherein may be accomplished in desiccated air as well as in dry nitrogenor other non-chemically active gases. Dry nitrogen, however, ispreferred.

[0058] In a preferred method of preparation of the dimetal sulfonylamide salt (III), CF₃SO₂NH₂ is dissolved at a concentration in the rangeof 5-10% by weight in acetonitrile in an inert atmosphere such asnitrogen. At higher concentrations good mixing may become more difficultto maintain as the insoluble CF₃SO₂NNa₂ product begins to form, creatinga dispersion. Therefore at concentrations higher than about 10% byweight, other forms of agitation may be preferred over simple stirring,such as ultrasonic agitation, or microfluidization such as may beachieved using a MicroFluidizer™ available from Microfluidics, Inc.,Newton, Mass.

[0059] While maintaining the inert atmosphere, NaH is added withagitation continued until the reaction is complete in about 4 hours.Hydrogen gas evolution rate, determined by any convenient method knownin the art, has been found to be an effective indicator of reaction. Thecessation of hydrogen gas flow signals completion of the reaction.

[0060] The amount of NaH added depends upon the particular requirementsand intentions of the practitioner hereof. Adding a slight excess overthe stoichiometric amount of NaH ensures complete conversion of theCF₃SO₂NH₂ or CF₃SO₂NHNa to CF₃SO₂NNa₂. However, this leaves CF₃SO₂NNa₂so prepared still contaminated with insoluble NaH from which it isdifficult to separate. However, it has been found that residual NaH islargely inert in the process of the invention and to the productsthereof. On the other hand, if the goal is to achieve the cleanestpossible CF₃SO₂NNa₂ then a slight deficit of NaH below thestoichiometric amount may be employed to ensure that the NaH will befully consumed. Employing a deficit of NaH will result in less thancomplete conversion of the CF₃SO₂NH₂ or CF₃SO₂NHNa to CF₃SO₂NNa₂. Thesoluble residual intermediary CF₃SO₂NHNa is easily washed away from theinsoluble CF₃SO₂NNa₂.

[0061] The dimetal sulfonyl amide salt (III) may be dried under vacuumat elevated temperature but the user must be aware of the possibility ofspontaneous and violent decomposition of the material. It is highlyrecommended to never handle this material in a totally dry state. It ishighly recommended to keep the material wet at all times. It seems thatthe smaller composition CF₃SO₂NNa₂ is less stable than the compositionsof higher molecular weight like C₄F₉SO₂NNa₂A suitable temperaturedepends upon the specific composition thereof. The preferred CF₃SO₂NNa₂should be dried at a temperature preferably not higher than 80° C., mostpreferably not higher than 65° C. Certain of the compositions of theinvention, including the preferred CF₃SO₂NNa₂, have been observed toundergo certain decomposition aggressively when heated to thedecomposition threshold but it has also been observed at one occasionthat the preferred CF₃SO₂NNa₂ undergoes spontaneous decomposition atroom temperature. The compound is moisture sensitive and should behandled under anhydrous conditions. It is believed that the product issomewhat unstable, and potentially may be subject to explosivedecomposition.

EXAMPLES EXAMPLE 1

[0062] CF₃SO₂NH₂was purchased from Tokyo Chemical Industry, Portland,Oreg., (TCI) and dried and purified by two cycles of sublimation under avacuum of about (0.1 Pa, 10⁻³ Torr), employing a water cooled (˜20° C.)cold-finger, and an oil bath at 80° C. Anhydrous acetonitrile waspurchased from EM Science Gibbstown, N.J., slurried with P₂O₅ anddistilled to ensure dryness, and stored over molecular sieves inside adry box until ready to be used. Sodium hydride (95%) was purchased fromAldrich Chemical.

[0063] Inside a model HE-63-P dry-box (Vacuum Atmosphere Company,Hawthorne, Calif.) having a dry nitrogen atmosphere, a round bottomflask was charged with 30.003 g of the sublimed CF₃SO₂NH₂ and 750 ml ofthe dried acetonitrile. 9.003 g of the sodium hydride was slowly addedover a period of 60 min while the reaction mixture was stirred with amagnetic stir bar. The temperature of the reaction mixture increasedfrom 21.6° C. to 50.5° C. during the addition process. The mixture wasstirred at room temperature for 20 h. After about 4-5 hours the reactionmedium had taken on an opaque “creamy” appearance, and no furtherbubbling, indicative of the evolution of hydrogen, was observed.

[0064] The reacted mixture was filtered through a glass-filter (mediumporosity) inside the dry-box. The white solid was washed three timeswith 100 ml of the anhydrous acetonitrile, transferred from the filterto a Schlenk flask and dried under vacuum (1 Pa, 10⁻² Torr) at roomtemperature for 5 h, still in the dry box. Approximately 10% of thefiltrate was lost in transferring from the filter to the Schlenk flask.The Schlenk flask was sealed, removed from the dry-box, and subject tofurther evacuation under oil pump vacuum (0.1 Pa, 10⁻³ Torr) for 15 h atroom temperature. The Schlenk flask was then immersed in an oil bath setat 50° C. and held for four hours at which time the bath was heated to65° C. and the 20 Schlenk flask was held therein for an additional 20 hwhile still subject to evacuation under oil pump vacuum (0.1 Pa, 10⁻³Torr). Afterwards, the CF₃SO₂NNa₂ was only handled inside the dry-box.30.0 grams of product were isolated. The product decomposed at 110° C.while generating large amounts of a gas.

[0065] It has been observed at one occasion that the preferredCF₃SO₂NNa₂ undergoes spontaneous decomposition at room temperature andit is therefore recommended to not dry this material but instead keep itas a suspension at all times.

EXAMPLE 2

[0066] Inside the dry box of Example 1, a flask was charged with 5.142 gC₄F₉SO₂NH₂ made from C₄F₉SO₂F and NH₃ according to the method ofMeuBdoerffer et al, op. cit., and 100 ml of anhydrous acetonitrileprepared as in Example 1. 0.784 g NaH (Aldrich) was slowly added over aperiod of 5 min. The mixture was stirred at room temperature for 24 hwithout observation. Insoluble C₄F₉SO₂NNa₂ had precipitated at thebottom of the flask. The reaction mixture was filtered through a glassfilter (fine porosity) and the white residue was washed three times with50 ml of anhydrous acetonitrile. The residue was collected from thefilter and placed in a Schlenk-flask. Afterwards, the material wasbrought outside the dry-box and dried under oil pump vacuum (0.1 Pa,10⁻³ Torr) for 24 h at an oil bath temperature of 65° C. C₄F₉SO₂NNa₂ wasonly handled inside the dry-box. 4.37 g of product were isolated.

[0067] It has been observed at one occasion that the preferredCF₃S0₂NNa₂ undergoes spontaneous decomposition at room temperature andit is therefore recommended to not dry this material but instead keep itas a suspension at all times.

EXAMPLE 3

[0068] Employing the reagents and equipment of Example 1, inside thedry-box 3.123 g of the sublimed CF₃SO₂NH₂ was dissolved in 100 ml of theanhydrous acetonitrile in a round-bottom flask. 1.127 g of the sodiumhydride was slowly added to form a first reaction mixture. Addition ofNaH took place over a period of 10min while the first reaction mixturewas stirred with a magnetic stirning bar at room temperature. After 3 h,no fluorine could be detected by ¹⁹F NMR in the solution indicatingcomplete conversion of CF₃SO₂NH₂ to CF₃SO₂NNa₂, thereby forming amixture of CF₃SO₂NNa₂ and acetonitrile, with some residual NaH.

[0069] CF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂F (PSEPVE) prepared according to themethod of Connolly et al., U.S. Pat. No. 3,282,875, was slurried withP_(2O) ₅ and distilled. 10.002 g of the thus-treated PSEPVE was added tothe mixture of CF₃SQ₂NNa₂ and acetonitrile prepared as hereinabove toform a second reaction mixture. The second reaction mixture was stirredat room temperature. After 10 min, the mixture turned clear, indicativeof complete reaction of the CF₃SO₂NNa₂, and then slightly cloudy,indicative of the precipitation of the NaF by-product After 30 minutesfluorine NMR confirmed a substantial concentration of the imidized formof PSEPVE. The reacted mixture was centrifuged and then filtered througha glass filter (medium porosity). The residue was washed with 100 ml ofanhydrous acetonitrile. All volatiles were removed under vacuum of 0.1Pa, 10⁻³ Torr at room temperature and the slightly beige residue washeated to 110° C. for 16 h at 0.1 Pa, 10⁻³ Torr. Yield was 9.494 g.

[0070]¹⁹F NMR in CD₃CN confirmed the structureCF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂N(Na)SO₂CF₃. ¹⁹F NMR in CD₃CN/Freon-11(CF₂A,A′=CFBOCF₂ ^(C)CF^(D)(CF₃ ^(E))OCF₂ ^(F)CF₂ ^(G)SO₂N(Na)SO₂CF₃^(H)): −112.6, −120.9 ppm (A, 1F, A′, 1F), −135.7 ppm (B, 1F), −78.0 ppm(CF₂, C₂,C, 2F), -144.2 ppm (CF, D, 1F), -79.1 ppm (CF₃, E, 3F), -83.7ppm (CF₂, F, 2F). -116.0 ppm (CF₂, G, 2F), -78.9 ppm (CF₃, H, 3F). MS:Negative electron spray; 574.14, M-Na.

EXAMPLE 4

[0071] Inside the dry-box of Example 1, a round bottom flask was chargedwith 5.027 g of the C₄F₉SO₂NH₂ made from C₄F₉SO₂F and NH₃ according tothe method of MeuBdoerffer et al, op.cit., and 100 ml of anhydrousacetonitrile prepared as in Example 1. 0.890 g of sodium hydride(Aldrich) was slowly added to form a first reaction mixture. Addition ofNaH took place over a period of 10 min while the reaction mixture wasstirred at room temperature with a magnetic stir bar. After 22 h ofsiring, no fluorine could be detected by ¹⁹F NMR in the solutionindicating complete conversion, thereby forming a mixture of C₄F₉SO₂NNa₂in acetonitrile, contaminated by some residual NaH.

[0072] 7.797 g of the PSEPVE of Example 3 was added to the mixture ofC₄F₉SO₂NNa₂ and acetonitrile prepared hereinabove to form a secondreaction mixture. The second reaction mixture was stirred at roomtemperature. After 10 min, the mixture turned clear, indicative ofcomplete reaction of the CF₃SO₂NNa₂, and then slightly cloudy,indicating the precipitation of the NaF by-product. NMR of the reactionmixture taken after 30 min confirmed the substantial presence of theimidized form of PSEPVE. The reaction mixture was centrifuged and thenfiltered through a glass filter (medium porosity). The residue waswashed with 100 ml of anhydrous acetonitrile. All volatiles were removedunder vacuum and the slightly beige residue was heated to 110° C. for 16h at 1 Pa, 10⁻³ Torr. Yield was 8.358 g.

[0073]¹⁹F NMR in CD₃CN confirmed the structureCF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂N(Na)SO₂(CF₂)₃CF₃ ¹⁹F NMR in CD₃CN/Freon- 11(CF₂A,A′CFBOCF₂ ^(C)CF^(D)(CF₃ ^(E))OCF₂FCF₂ ^(G)SO₂ N(Na)SO₂CF₂HCF₂CF₂^(J)CF₃ ^(K)): -112.6, -120.7 ppm (A, 1F, A′, 1F), -135.6 ppm (B, 1F),-78.0 ppm (CF₂, C, 2F), -144.1 ppm (CF, D, 1F), -79.1 ppm (CF₃, E, 3F),-83.7 ppm (CF₂, F, 2F), -115.9 ppm (CF₂, G, 2F), -112.6 ppm (CF₂, H, 2F2-120.6 ppm (CF_(2,) I, 2F), -125.8 ppm (CF₂, J, 2F), -79.1 ppm (CF₃, K,3F). MS: Negative electron spray; 723.98, M-Na.

EXAMPLE 5

[0074] Benzonitrile (Aldrich)was dried by mixing with P₂O₅ and thendistilling. Employing reagents and equipment of Example 1, inside thedry-box 3.008 g of the sublimed CF₃SO₂NH₂ was dissolved in 90 ml of thedried benzonitrile in a round-bottom flaskt To form a first reactionmixture, 1.018 g of the sodium hydride was slowly added while thereaction mixture was stirred with a magnetic stirring bar at roomtemperature. The reaction mixture changed its appearance after 10 min. Awhite precipitate was formed causing a thickening of the slurry. Shortlyafter, the reaction mixture changed its color to yellow. After 60 min,the reaction mixture was red. After 6 h, fluorine could still bedetected by ¹⁹F NMR in the solution. After a total of 24 h at roomtemperature, 8.511 g of PSEPVE of Example 3 was added, thereby forming asecond reactions mixture. The second reaction mixture was stirred atroom temperature. The color changed from red to yellow. ¹⁹F NMR in CD₃CNafter 2 h confirmed the formation of the structureCF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂N(Na)SO₂CF₃.

EXAMPLE 6

[0075] In this Example, an apparatus was employed for determining thevolume of hydrogen gas evolved by the reaction as a function of time.The apparatus is depicted in FIG. 1. One neck of a three necked roundbottom flask, 1, holding a magnetic stirring bar, 2, was fitted with asolid reactant addition device SRAD, 3, having a 75° angle to beemployed for feeding a solid to the flask. A second neck was fitted witha thermocouple probe, 4, and a third neck was fitted with a stopcock, 5.The stopcock, 5, was connected via a 4 cm piece of Tygon® tubing, 6, toan Aldrich Safe-purge (TM) valve, 7, containing mineral oil. TheSafe-purge valve, 7, was connected via a rubber hose, 8, to awater-filled 250 ml graduated cylinder, 9, that is deployed upside-downin a water-filled 600 ml beaker, 10. In operation liquid reactants werecharged to the flask through any of the necks, SRAD, 3, was charged withthe desired amount of solid reactant and reaffixed to the flask, 1, inthe downward-pointing position shown in the figure. The beaker, 10, wasfilled to about 50% of capacity with water while the graduated cylinder,9, was filled completely with water. The stopcock, 5, was opened, andthe adaptor, 3, was inverted thus delivering the solid reactant to thereactants in the flask and thereby initiating the reaction. As hydrogenwas evolved from the reaction it displaces the water from the graduatedcylinder providing a volumetric means for determining the rate and totalamount of hydrogen evolution.

[0076] Employing the methods and material of Example 1, inside thedry-box, 0.546 g of the sublimed CF₃SO₂NH₂ was dissolved in 100 ml ofthe anhydrous acetonitrile in the three neck round bottom flask ofFIG. 1. 0.213 g of the sodium hydride was carefully placed in the SRAD.The flask was carefully brought outside the dry box and connected to theremainder of the apparatus of FIG. 1. After all connections had beenestablished, the stopcock to the reaction flask was opened. The reactionmixture was stirred at room temperature and the SRAD was invertedthereby feeding the NaH to the solution in the flask. Immediately, areaction could be observed. 80 ml of gas were collected over a period of5 min. The temperature of the reaction mixture increased from 23° C to26° C. Over the next 120 min, the formation of gas slowed down and 74 mlof gas were collected in the graduated cylinder. During this period, theappearance of the reaction mixture changed. The fine residue in thereaction mixture changed to a thicker precipitate that settled easily tothe bottom of the flask when the stirring was stopped. The reactionmixture was stirred for another hour at room temperature, 10 ml ofadditional gas were collected during this period. The flask was broughtinto the dry box and a sample of the solution was submitted for NMR. Nofluorine could be detected, indicating the complete conversion ofCF₃SO₂NHNa into insoluble CF₃SO₂NNa₂.

EXAMPLE 7

[0077] Excess CF₃SO₂NH₂ and NaOH were reacted in water to prepareCF₃SO₂NNaH. Water and excess CF₃SO₂NH₂ were removed under vacuum (0.1Pa, 10⁻³ Torr) at 70° C.; the residue was dried for 16 h at 0.1 Pa, 10⁻³Torr at 110° C. Following the procedures of Example 1, inside the drybox, a 250 ml two neck round bottom flask with a magnetic siring bar wascharged with 1.034 g of the CF₃SO₂NNaH. The material was dissolved in100 ml of anhydrous acetonitrile of Example 1. The procedures of Example10 were followed but the three necked flask was replaced by thetwo-necked flask and the thermocouple was omitted. The reaction mixturewas stirred at room temperature and the SRAD was inverted therebyfeeding the NaH to the solution in the flask. No immediate reactioncould be observed. Over the first 150 min, only a total of 10 ml of anevolving gas could be collected. After 150 min, the formation of gasstarted. Over the next 105 min, additional 135 ml of gas were collectedin the graduated cylinder. During this period, the appearance of thereaction mixture changed. The fine residue in the reaction mixturechanged to a thicker precipitation that settled easily at the bottom ofthe flask when the stirring was stopped. The reaction mixture wasstirred for another 14 h at room temperature. 10 ml of additional gaswere collected during this period. The flask was brought into the drybox and a sample of the solution was submitted for NMR No fluorine couldbe detected, indicating the complete conversion of CF₃SO₂NHNa intoinsoluble CF₃SO₂NNa₂.

EXAMPLE 8

[0078] Following the procedure of Example 10, inside the dry-box, a 250rnl three neck round bottom flask was charged with 75 ml of anhydrousacetonitrile prepared as in Example 1. 0.189 g NaH was placed in theSRAD. 0.879 g of the CF₃SO₂NHNa of Example 10 was dissolved in 25 mlacetonitrile prepared as in Example 1 and placed in an addition fimnelwhich substituted for the thermocouple of Example 10. After the requiredconnections were made, the reaction mixture was stirred at roomtemperature and the NaH was immediately added to the solvent. 6 ml ofgas were collected over a period of 3 h. The CF₃SO₂NHNa solution wasadded and the reaction mixture was continued to be stirred at roomtemperature. 1 h 45 min after the addition of the CF₃SO₂NHNa, anadditional 4 ml of gas had been collected. The reaction mixture turnedslightly yellow. 4 h after the addition of the CF₃SO₂NHNa, the reactionseemed to start. 6 h and 40 min after the addition of the mono-sodiumsolution, a total of 80 ml of gas since the addition had been collected.The reaction mixture was sired for another 14 h 30 min. A total of 116ml gas had been collected. 103 ml are the expected amount The flask wasbrought into the dry-box and an NMR sample was collected from thesolution. Only a trace of a fluorine signal at −80.6 ppm could bedetected, indicating the conversion of CF₃SO₂NHNa into insolubleCF₃SO₂NNa₂.

[0079] 2.120 g PSEPVE was added to the now bright yellow solution,containing a yellowish solid. The reaction mixture turned orange andafter 15 min stirring at room temperature, the reaction mixture turnedclear. A fine precipitate formed. An NMR sample was collected after 1 hshowing the formation of the productCF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂N(Na)SO₂CF₃ and excess PSEPVE.

COMPARATIVE EXAMPLE 1

[0080] Inside the dry-box of Example 1, a flask was charged with 0.93 gof CF₃SO₂NHNa from Example 11, 0.135 g NaH (Aldrich) and 20 ml ofanhydrous nIF (Aldrich; distilled off Na metal). The reaction mixturewas stirred for 4 h at room temperature and was then filtered through aglass filter (fine porosity). The filtrate was collected in a flask andbrought outside the dry-box. All solvents were removed under vacuum (0.1Pa, 10⁻³ Torr) and the residue was heated to 65° C. for 24 hat 0.1 Pa,10⁻³ Torr. 0.862 g (5.04 mmol) of CF₃SO₂NENa were recovered,corresponding to 92.6% of the staring material. The dried material wasbrought into the dry-box and 50 ml of anhydrous acetonitrile were addedbecause it is suspected that CF₃SO₂NNa₂ is slightly soluble in THIF. Themajority of the material was dissolved in the acetonitrlle and only aslight trace of a solid could be observed in the solution. It was notattempted to separate this residue. It should be safe to assume thatless than 10% of the CF₃SO₂NHNa have been converted to CF₃SO₂NNa₂ after4 h in THF at room temperature.

EXAMPLE 9

[0081] Following the procedures of Example 11, inside the dry-box, theround bottom flask was charged with 0.866 g of the CF₃SO₂NHNa of Example11. The material was dissolved in 100 ml of anhydrous THF (Aldrich;distilled from Na metal; stored over molecular sieves inside thedry-box). 0.171 g of NaH was placed in the SRAD. After the requiredconnections were made according to Example 10, the reaction mixture wasstirred at room temperature and the NaH was added to the solution. Noobvious reaction could be observed. A total of 113.3 ml of collectedhydrogen would represent complete conversion under normalizedconditions. The gas collected as a function of time is shown in Table 1.TABLE 1 Elapsed time Gas Collected estimated % (after addition of NaH)(ml) conversion  0 h 45 min 4 3.5  2 h 30 min 10 8.8  5 h 45 min 10 8.8 21 h 45 min 18 15.9  26 h 15 min 25 22.1  32 h 45 min 28 24.7  47 h 3833.6  49 h 15 min 43 38.0  53 h 30 min 47 41.6  84 h 45 min 53 46.9  86h 45 min 55 48.6  97 h 15 min 65 57.5 118 h 78 69.0 122 h 15 min 85 75.2139 h 45 min 110 97.3 142 h 114 100.5

[0082] The reaction was completed after six days at room temperature.The reaction flask was brought inside the dry-box.

[0083] 2.511 g PSEPVE was added to the colorless reaction mixture thatcontained a white solid. After 10 min stirring at room temperature, thereaction mixture turned clear. A fine precipitation formed. An NMRsample was collected after 1 h showing the formation of the productCF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂N(Na)SO₂CF₃ and excess PSEPVE.

EXAMPLE 10

[0084] Following the procedure of Example 11, inside the dry-box, theround bottom flask was charged with 0.633 , of the CF₃SO₂NHNa of Example11. The material was dissolved in 100 ml of anhydrous acetonitrileprepared as in Example 1. 0.103 g of NaH was placed in the SRAD. Afterthe required connections were made, the reaction mixture was stirred andheated by immersing the flask in an oil-bath set at 50° C. The reactionmixture was heated for 2 h and the pressure was allowed to equalizeinside the flask. No pressure was released through the bubbler for 30min. After 2 h of heating, the NaH was added to the solution. No obviousreaction could be observed for 20 min.. After 20 min., gas was releasedfrom the reaction mixture. Evolution of ca. 83 ml of gas was calculatedto correspond to complete conversion. TABLE 2 Elapsed time Gas Collected(after addition of NaH) (ml) 0 h 20 min 0 0 h 25 min 25 0 h 30 min 71 0h 35 min 85 1 h  0 min 91

[0085] The formation of gas stopped after 1 hour. The gas collectionrecord is shown in Table 2. The reaction mixture was stirred for anotherhour at 50° C oil bath temperature with no further accumulation of gas.The reaction flask was brought inside the dry-box and an NMR sample wastaken from the clear solution above the white residue. Only a trace of afluorine signal at −80.6 ppm could be detected in the noise of the NMRspectrum, indicating the conversion of CF₃SO₂NHNa into insolubleCF₃SO₂NNa₂.

[0086] 1.740 g PSEPVE was added to the colorless reaction mixture thatcontained a white solid. The reaction mixture turned yellow and after 10min stirring at room temperature, the reaction mixture turned clear. Afine precipitation formed. An NMR sample was collected after 1 h showingthe formation of the product CF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂N(Na)SO₂CF₃ andexcess PSEPVE.

EXAMPLE 11

[0087] Following the procedure of Example 10, the flask was charged with1.195 g of the CF₃SO₂NHNa which was dissolved in a mixture of 95 ml ofTHF and 5 ml of anhydrous acetonitrile. 0.195 g of the NaH were placedin the SRAD. After connection to the remainder of the apparatus ofExample 10, the NaH was added to the reactants in the flask. Noimmediate reaction could be observed. Over the first 1 h, only a totalof 4 ml of gas was evolved. Over the next 5 h, only a total of 7 ml ofthe expected 157 ml. Hydrogen gas had been collected. The reactionmixture was stirred for a total of 25 h at room temperature withoutfurther observation. 160 ml of gas were collected during this period.4.500 g PSEPVE was added to the colorless reaction mixture thatcontained a white solid. The reaction mixture did not change its colorand after 10 min stirring at room temperature, the reaction mixturetunied clear. A fine precipitation formed. An NMR sample was collectedafter 1 h showing the formation of the productCF₂CFOCF₂CF(CF₃)OCF₂CF₂SO₂N(Na)SO₂CF₃ and excess PSEPVE.

EXAMPLE 12

[0088] Employing the reagents and equipment of Example 1, inside thedry-box 3.033 g of the sublimed CF₃SO₂NH₂ was placed in a round bottomflask and dissolved in 50 ml of the anhydrous acetonitrile. 1.51 1 g ofCaH₂ (Aldrich; 90-95%) was added. The reaction mixture was stirred witha magnetic stir bar at room temperature for 48 h. No fluorine could bedetected in the reaction mixture after this time period by NMR,indicating the complete conversion of CF₃SO₂NH₂ to (CF₃SO₂NCa)₂.

[0089] 9.461 g of distilled PSEPVE was added and the reaction mixturewas stirred at room temperature. No conversion to the product could beobserved after 24 h at room temperature.

[0090] The reaction mixture was heated to 60° C. for 7 days. Thereaction mixture was filtered inside the dry-box through a glass filter(medium porosity) and the flask with the collected solution was broughtoutside the dry-box. All volatiles were removed under vacuum (0.1 Pa,10⁻³ Torr) and the beige residue was heated to 100° C. at 0.1 Pa, 10⁻³Torr for 16 h. ¹⁹F NMR in CD₃CN confirmed the structure(CF₂=CFOCF₂CF(CF₃)OCF₂CF₂SO₂NSO₂CF₃)₂Ca. Yield was 1.729 g. ¹⁹F NMR inCD₃CN (CF₂ ^(A,A)′=CF^(B)OCF₂ ^(C)CF^(D)(CF₃ ^(E))OCF₂ ^(F)CF₂^(G)SO₂NSO₂CF₃ ^(H))₂Ca: -114.3, -122.7 ppm (A, 1F, A′, 1F), -137.3 ppm(B, 1F), -79.5 ppm (CF₂, C, 2F), -145.9 ppm (CF, D, 1F), -80.9 ppm (CF₃,E, 3F) -85.5 ppm (CF₂, F, 2F), -117.6 (CF₂, G, 2F), -80.6 ppm (CF₃, H,3F). MS: Negative electron spray; 573.98, (M-Ca)/2.

EXAMPLE 13

[0091] Inside the dry-box, a round bottom flask was charged with 3.051g, of the CF₃SO₂NH₂ prepared in the manner of Example 1 and 100 ml ofanhydrous acetonitrile prepared as in Example 1. 1.068 g of the NaH(Aldrich) was added slowly over a period of 5 min. The mixture wasstirred at room temperature for 26 h inside the dry-box and checkedperiodically by fluorine NMR until no fluorine could be detected. 3.27 gC₆H₅SO₂F used as received from Aldrich was added to the flask. Thereaction mixture thus formed was stirred at room temperature for 144 h.The reaction mixture was centrifuged and all volatiles were removed fromthe reaction solution. The residue was dried at 110® C. for 24 h at 0.1Pa, 10⁻³ Torr. The residue was redissolved in 100 ml of anhydrousacetonitrile and filtered through a paper filter. All volatiles wereremoved from the solution. The residue was dried at 110° C. for 16 h at0.1 Pa, 10⁻³ Torr. NMR in CD₃CN and mass spec. confirmed the structurePhSO₂N(Na)SO₂CF₃. Yield was 4.284 g. ¹⁹F NMR in CD₃CN: -79.9 ppm (CF₃,3F). ¹H NMR in CD₃CN: 7.90 ppm (2H), 7.54 ppm (3H). MS: negativeelectron spray; 288.09, M-Na.

EXAMPLE 14

[0092] As in Example 1, a round bottom flask was charged with 3.082 g ofthe CF₃SO₂NH₂ prepared as in Example 1 and 100 ml of anhydrousacetonitrile prepared as in Example 1. 1.134 g of the NaH (Aldrich) wasadded slowly over a period of 5 min. The mixture was stirred at roomtemperature for 16 h inside the dry-box. No fluorine could be detectedby NMR 2.025 g of CH₃SO₂F (Aldrich, as received) was added. The reactionmixture thus formed was stirred at room temperature for 2 h. Thereaction rnixture was centrifliged and all volatiles were removed. Theresidue was dried at 110° C. for 24 h at 0.1 Pa, 10⁻³ Torr. The residuewas redissolved in 100 ml of anhydrous acetonitrile and filtered througha paper filter. All volatiles were removed from the solution. Theresidue was dried at 110° C. for 16 h at 0.1 Pa, 10⁻³ Torr. Yield was4.20 g. NMR in CD₃CN and mass spec. confirmed the structureCH₃SO₂N(Na)SO₂CF₃. ¹⁹F NMR in CD₃CN: -79.7 ppm (CF₃, 3F). ¹H NMR inCD₃CN: 2.966 ppm (3H). MS: negative electron spray; 226.06, M-Na.

EXAMPLE 15

[0093] A 400 mL Hastelloy autoclave prechilled to <−20° C. was chargedwith PSEPVE (150 g) and 15 mL of 0.17 M hexafluoropropylene oxide dimerperoxide. The vessel was closed, evacuated, then fiiter charged withvinylidene fluoride (64 g) and CO₂ (150 g), and shaken at roomtemperature for 18 hr. Excess pressure was released and the viscousresidue was analyzed by ¹⁹F NMR (acetone d₆) which clearly indicatedresidual monomer. Estimated conversion of PSEPVE was ca 60%. The entiresample was devolatilized at 100° C. (0.5 mm) for several hours. Samplewas a rather tough rubber, deformable by application of force. It didnot flow significantly at room temperature under its own weight.

[0094]¹⁹F NMR (acetone d₆): +45.5 (s, a=0.91), −77.5 to −79.8 (m,a=7.00), −91 to −95.5 (m, a =4.038), −108 to −115.9 (m, a=4.680),−121.8, −122.3, and −122.8 (series of broadened m's. a=1.651), −124 to−127 (bd m's, a =0.766), −129.5 (s, a=0.0244, assigned to internal CF₂of CF₃CF₂CF₂OCF(CF₃)-fragment (end s group), −144 (bd , CF from PSEPVEside chains). Integration was consistent with 24.5 mol % PSEPVE.Integration of end groups from dimer peroxide fragments, assuming thatall ends are of this type, gives an estimate of M_(n) for the copolymeras 106,000. ¹H NoM showed only broad signal 3.5-2.7. 4.47 g of thecopolymer so prepared was dried at 0.1 Pa, 10⁻³ Torr for 24 h at 100° C.100 ml of anhydrous THF was added to the polymer and the reactionmixture was refluxed for 16 h to dissolve the polymer. 1.344 g of theCF₃SO₂NNa₂ prepared in Example 1 were added at room temperature over aperiod of 2 h. The reaction mixture was stirred at room temperature. Thereaction mixture turned cloudy after 3 h. An additional 0.418 g ofCF₃SO₂NNa₂ was added over the next 6 days. After all the CF₃SO₂NNa₂ wasadded, the reaction mixture so formed was heated to 50° C. After 3 daysat 50° C., ¹⁹F NMR indicated that the reaction was complete.

[0095] The reaction mixture was brought outside the dry-box andcentrifuged. A slightly brown solution could be separated from a darkbrown residue. Analysis of the residue showed that it was mostly NaF andexcess CF₃SO₂NHNa starting material. All volatiles were removed from thecombined solutions and the beige residue was heated to 110° C. at 0.1Pa, 10⁻³ Torr for 16 h. Yield is 3.8 g. ¹⁹F NMR in d₈-TEF confimedcomplete conversion of the sulfonyl fluoride groups of the polymer toimide. ¹⁹F NMR Residue in d₈-THF; −79 to −85 ppm (CF₃SO₂, CF₃(CF),2×CF₂O, 10 F), −90 to −135 ppm (CF₂SO₂, VF₂ florines), −146.0 ppm(CF(CF₃), 1F); integration gives 28 mol % PSEPVE-imide in the polymer.¹H NMR Residue in d₈-THF: 2 to 3.8 ppm VF2 protons.

EXAMPLE 16

[0096] CH₂=CHCH₂CF₂CF₂OCF₂CF₂SO₂F was synthesized according to theteachings of Guo et al., Huaxue Xuebao (1984),42(6), 592-5.

[0097] As in Example 1, a round bottom flask was charged with 2.02 g ofCF₃SO₂NNa₂ prepared as in Example 1 and 60 ml of anhydrous acetonitrilcprepared as in Example 1. 3.73 g CH₂=CHCH₂CF₂CF₂0CF₂CF₂SO₂F was addeddrop wise over a period of 5 min. After 20-25 min, the mixture turnedclear and then generated a precipitation. The mixture was stifred for 3h at room temperature. The reaction mixture was filtered through a paperfilter inside the dry box. All volatiles were removed and the whiteresidue was heated to 100° C. for 16 h at 0.1 Pa, 10⁻³ Torr. Yield was3.635 g. ¹⁹F NMR in CD₃CN conimed the stuctureCH₂=CHCH₂CF₂CF₂OCF₂CF₂SO₂N(Na)SO₂CF₃. ¹⁹F NMR in CD₃CN:CH₂=CHCH₂CF₂ACF₂BOCF₂CCF₂DSO,N(Na)SO₂CF₃E: −80.60 ppm (CF₃, E, 3F),−82.77 ppm (CF₂, C, 2F), −88.90 ppm (CF₂, B, 2F), −118.31 ppm (2 X CF₂,A +D, 4F). ¹H NMR in CD₃CN: CH₂A=CHBCH₂CCF₂CF₂OCF₂: 2.87 ppm (CH₂, C,tdt, 2H), 5.26 ppm (CH₂, A, 2F) and 5.74 ppm (CH₂, B, 1F).

I claim:
 1. A process comprising: contacting in a liquid dispersion orsolution a composition comprising a dimetal sulfonyl amide saltrepresented by the formula (R²SO₂NM_(b))_(3-b)M′_(c) wherein R² is aryl,fluoro-aryl, or XCF₂-where X is H, halogen, fluorinated ornon-fluorinated linear or cyclic alkyl radicals having 1-10 carbons,optionally substituted by one or more ether oxygens, M′ is an alkalineearth metal, b=1 or 2, c=0 or 1, M is an alkaline earth where b is 1 oran alkai metal where b is 2 and c=0, and M is alkali metal when b=1 andc=1, with the proviso that c is not equal to 1 when b=2 with anon-polymeric sulfonyl fluoride composition represented by the formulaR¹(SO₂F)_(m) wherein m=1 or 2, where when m=1 R¹ is a fluorinated ornon-fluorinated, saturated or unsaturated hydrocarbyl radical exceptperfluoroolefin having 1-12 carbons optionally substituted by one ormore ether oxygens, or tertiary amino; or, when m=2, R¹ is a fluorinatedor non-fluorinated, saturated or unsaturated hydrocarbylene, exceptperfluoroalkylene, radical having 1-12 carbons optionally substituted byone or more ether oxygens; or with a polymeric sulfonyl fluoridecomposition comprising monomer units represented by the formula —[CZ ₂CZ(R ³ SO ₂ F)]— wherein R³ is a diradical selected from the groupconsisting of fluorinated or non-fluorinated alkylene, includingoxyalkylene or fluorooxyalkylene, but not perfluoroalkylene, and each Zis independently hydrogen-oraogen, and need not be the same; and,causing them to react to form a non-polymeric imide compositionrepresented by the formula

wherein y 1 or 2, M is alkali or alkaline earth metal when y is 1 or 2respectively, m=1 or 2, where, when m=1, R¹ is a fluorinated ornon-fluorinated, saturated or unsaturated hydrocarbyl radical, exceptpeifluoroolefin, having 1-12 carbons optionally substituted by one ormore ether oxygens, or tertiary amino; or, when m=2, R¹ is a fluorinatedor non-fluorinated, saturated or unsaturated hydrocarbylene, exceptperfluoroalkylene, radical having 1-12 carbons optionally substituted byone or more ether oxygens, with the proviso that when y=2 and m=2, M mayrepresent a combination of alkali and alkaline earth metals; or, in thealternative, a polymeric imide composition comprising monomer unitsrepresented by the formula

wherein y=1 or 2; R³ is a diradical selected from the group consistingof fluorinated or non-fluorinated alkylene, including oxyalkylene orfluorooxyalkylene, but not perfluoroalkylene, each Z is independentlyhydrogen or halogen, wherein the Zs need not be the same; R² is aryl,fluoro-aryl, or XCF₂-where X is H, halogen, fluorinated ornon-fluorinated linear or cyclic alkyl radicals having 1-10 carbons,optionally substituted by one or more ether oxygens; M is an alkali wheny is 1 or an alkaline earth metal when y is
 2. 2. The process of claim 1wherein m=1.
 3. The process of claim 1 further comprising an inert,aprotic organic liquid.
 4. The process of claim 3 wherein the organicliquid is an ether.
 5. The process of claim 4 wherein the raher istetrahydrofuran.
 6. The process of claim 1 wherein R² is aperfluoroalkyl radical.
 7. The process of claim 6 wherein R² is atrifluoromethyl radical.
 8. The process of claim 1 wherein M is analkali metal, b=2 and c=0.
 9. The process of claim 8 wherein M issodium.
 10. The process of claim 2 wherein R¹ is a perfluorovinyl etherradical.
 11. The process of claim 10 wherein the perfluorovinyl etherradical is represented by the formula CF ₂ =CF-O-[CF ₂ CF(R ⁴)-O_(z)]_(a)-CF ₂ CF ₂-wherein R⁴ is F or perfluoroalkyl having 1-4carbons, z=0 or 1, and a =0-3.
 12. The process of claim 11 wherein R⁴ istrifluoromethyl, z=1, and a=0 or
 1. 13. The process of claim 1 wherein Zis F.
 14. The process of claim 1 wherein R³ is a perfluorooxyalkyleneradical.
 15. The process of claim 14 where R³ is a perfluorooxyalkyleneradical represented by the formula -O-[CF ₂ CF(R ⁴)-O _(z)]_(a)-CF ₂ CF₂-wherein R⁴ is F or perfluoroalkyl having 1-4 carbons, z=0 or 1, anda=0-3.
 16. The process of claim 15 wherein R⁴ is trifluoromethyl, z=1,and a=0or
 1. 17. The process of claim 1 wherein the sulfonyl fluoridepolymer composition further comprises comonomer units derived from thegroup consisting of fluorinated, but not perfluorinated, olefins,non-fluorinated olefins, fluorinated vinyl ethers, non-fluorinated vinylethers, and mixtures thereof.
 18. The process of claim 17 wherein thecomonomer units are derived from the group consisting of ethylene,perfluoroalkyl vinyl ether, vinylidene fluoride, and vinyl fluoride, andmixtures thereof.
 19. The process of claim 18 wherein the comonomerunits comprise vinylidene fluoride.
 20. The process of claim 19 whereinthe vinylidene fluoride is at a concentration of at least 50 mol % inthe sulfonyl fluoride polymer composition.
 21. The process of claim 1wherein the monomer units represented by the formula -[CZ₂CZ(R³SO₂F)]-are present in the sulfonyl fluoride polymer at a concentration of up to50 mol %.
 22. The process of claim 21 wherein the monomer unitsrepresented by the formula -[CZ₂CZ(R³SO₂F)]- are pr,e set ifffhesulfonyl fluoride polymer at a concentration of up to 20 mol %.
 23. Theprocess of claim 9 fuiner comprising the step of performing an ionexchange to form the lithium imide.
 24. The process of claim 23 whereinthe ion exchange is performed by contacting the sodium imide withorganic lithium chloride solution.
 25. The process of claim 1 whereinthe composition comprising the dimetal sulfonyl amide salt comprises atleast 50 mol % of said dimetal sulfonyl amide salt.
 26. The process ofclaim 25 wherein the composition comprises at least 90 mol % of saiddimetal sulfonyl amide salt.
 27. The process of claim I wherein thedimetal sulfonyl amide salt is contacted with the non-polymeric sulfonylfluoride composition causing them to react to form the non-polymericimide composition.
 28. The process of claim 1 wherein the dimetalsulfonyl amide salt is contacted with the polymeric sulfonyl fluoridecomposition causing them to react to form the polymeric imidecomposition.
 29. The process of claim 18 wherein the sulfonyl fluoridepolymer composition further comprises a termonomer unit derived from aperfluoro-olefin.
 30. The process of claim 29 wherein the perfluorolefinis tetrafluoroethylene, hexafluoropropylene or a combination thereof